As summer comes to an end and we move into fall, cold and flu season beings. Chronic congestion, runny noses, fatigue and germs start to spread easily through training facilities, locker rooms, offices, and daycares as we move indoors during the colder, darker and shorter days of winter.

As you make performance gains in the gym or at the office, there is no worse feeling than having it derailed by a nasty cold or flu. It stops your progress in its tracks and halts your momentum on projects at work and home. So, what can you do this year to prevent how frequently you get a colds or flu, or if you do catch something, what can you do to dramatically reduce the severity and duration? I've listed below five common reasons people struggle through the fall and winter months, and what you can do about it.

1. You’re Over-Caffeinated

As the days get shorter, your body needs more rest and recovery. Coffee is a wonderful thing, but if you don't modify your intake and take your foot off the caffeine gas pedal during the fall and winter, you'll likely find yourself struggling to get up in the morning (i.e. how many times do you hit snooze?), a scratchy throat, dark circles under your eyes and other early symptoms of being rundown. You’re burning the candle at both ends, and by adding more stimulants to the mix, you tax your nervous system even further and leave yourself more prone to catching a cold or flu.(1)

Solution: If you are run down or feel like you're about to get sick take your foot off the accelerator and reduce your coffee intake by 50%. Also, you can think about taking 1-2 days off per week throughout the cold and flu season to give your nervous system a little break and your immune system a chance to recharge. If you're sick or constantly sick you need a caffeine break. Take a full week off all caffeine (no coffee, no tea, no chocolate... If the mere though of that makes you fearful, experience tells me you likely need it most!).

2. Stress Is Taxing Your Immune System

The days get shorter in fall and winter, but your schedule doesn't. In fact, for most people it ramps up. This mismatch between the shorter light exposure of the day, and your daily routine which starts before the sun comes up (and probably ends long after sundown) increases the overall stress on your body. Increased stress levels can suppress your “first line of defense” innate immune system - made up of neutrophils, macrophages, natural killer cells, etc - and leave you more susceptible to infection.(2)

Solution: Follow a seasonal diet. Pumpkins, squash, sweet potatoes, and carrots are loaded with innate immune boosting vitamin A and are all classic autumnal foods. Vitamin A is found in abundance in orange vegetables and including more of these foods in your nutritional arsenal will help to build mucosal immunity and keep your immune army strong throughout the fall and winter. Sow roast them in big batches to prep your lunches or dinner or puree them into soups to warm up and stay cold- and flu-free.

3. Your Vitamin D Is Too Low

Vitamin D status is a crucial factor for maintaining a healthy and robust immune response, up-regulating key antimicrobial protein that keep foreign bacteria and viruses at bay. Ancestral foods like eggs, pork, fish, and mushrooms contain some vitamin D, however it’s not enough to maintain your blood levels above 30ng/ml (the recommended level for the general population) if you live in a city with a true winter climate or north of the 49th parallel. In short, getting enough vitamin D during the coldest and darkest months of the year is really difficult from food alone.

If you’re training intensely, you also have a greater need for vitamin D. Intense exercise drives down vitamin D levels, and new research is uncovering how deficiency can lead to reduced muscular power production, V02 max (a measure of peak aerobic fitness), inflammation and recovery.(3) Based on the research, aim to maintain your levels above 40ng/ml throughout the year if athletic performance is your goal (the actual number may vary slightly depending on your ethnic background and melanin content of skin).

Solution: Supplement with 2,000-5,000 IU of a vitamin D3 daily (or equivalent weekly dose) to maintain your levels throughout the fall and winter months. If you’re supplementing at the top end of this range, get your levels tested every 8-12 weeks. Adding cod live oil - rich in omega-3s and vitamins A and D - is also a nice seasonal change to provide well-rounded support.

4. You Go To Bed Too Late

Research shows that sleeping less than 5 hours at night equals a 5-fold increased risk of catching a cold or flu, so make sure that, even during busy periods, you aren’t running on empty.(4) A recent study on modern day hunter-gatherer tribes – the San of southern Africa, the Tsimane in Bolivia and the Hadza in Tanzania – found they sleep an average the same number of hours recommended by the National Sleep Foundation, but their sleep habits change as the seasons change. The researchers found that in the shorter, darker days of winter the hunter-gatherer tribes went to bed about one and half hours earlier (i.e. 915pm) compared to the summer months (i.e. 10:45pm), yet they woke up around the same time throughout the year.(5)

Solution: Get to bed 1-hour earlier this fall. (Sounds easy, but it's actually quite difficult for many people.) Later bedtimes - and thus less total sleep - are often the result of staying up too late checking cellphones, working on laptops, or watching iPads. The blue light is stimulating and distracts you from how tired you truly are. Reboot your sleep and start your bedtime routine an hour earlier this fall; shut off all electronics by 900pm, turn down the lights in your house, switch to reading and add a warm cup of tea or bone broth to help wind down before bed.

5. You Don’t Wash Your Hands Enough

Yep, this is really a problem (especially in elite athletes!). Your mom or dad probably told you to wash your hands before every meal when you were young and the research shows it's really sound advice to prevent colds and flus.(6) Unfortunately, at work or in the gym most people forget this basic hygiene habit and dig straight into their meal. You end up touching your mouth or nose (without likely realizing), thus allowing the nasty bugs to penetrate your defences and wreak havoc in the body.

How important is hand washing? The World Health Organization (WHO) has issued repeated suggestions to “avoid shaking hands” for business people throughout the winter to avoid the rapid spread of germs.(7)

Solution: It’s simple... wash your hands before every meal! (Note – soap and water are just as effective as antimicrobial hand sanitizers.)

Stay ahead of the game this year. Don’t let frequent or nasty colds and flu slow your progress in the gym, at the office or home this year. Modify the areas listed above and you'll reduce your likelihood of getting sick, or at the very leas, reduce the severity and duration of colds if they do strike.

Dr. Marc Bubbs

Do you wake up feeling tired? Are you struggling to lose weight? Do you worry about aging or worsening health? Don’t let fatigue, a hectic life, or the way you look hold you back. Take control of your health and achieve your performance potential. It’s all here on the website...

Dr. Marc Bubbs ND, MS(c), CISSN, CSCS is a Naturopathic Doctor, Speaker, Director of Nutrition for the Canadian Men's National Basketball Team and former Strength Coach. Dr. Bubbs is the author of The Paleo Project: The 21st Century Guide to Looking Leaner, Getting Stronger, and Living Longerand a regular contributor to Re-Find Health, Breaking Muscle,PaleoDiet.com anda nutrition advisory board member forStrong Magazine. Dr. Bubbs regularly presents at health, fitness and medical conferences across Canada, USA, UK and Europe and has consulted with professional sports teams in the NBA, NFL, NHL and MLB.